Significance of Nutritional-Inflammatory Index as Predictors for Total Neoadjuvant Therapy-Induced Tumor Regression in Locally Advanced Rectal Cancer Patients

Purpose: To evaluate the predictive capacity of the nutritional-inflammatory index and clinicopathological characteristics in patients with locally advanced rectal cancer (LARC) receiving total neoadjuvant therapy (TNT). Methods: Data from 127 patients with LARC receiving TNT from January 2017 to January 2021 were retrospectively analyzed. Clinicopathological characteristics with different TNT-induced responses were compared. The Chi-square test and the Mann-Whitney test were used to analyze the association between pre-TNT factors and TNT-induced responses. Multivariable logistic regression analysis was used to construct a predictive model. Results: In the cohort of 127 patients with LARC who underwent total neoadjuvant therapy (TNT), the mean age was 54.1 +/- 11.4 years; 88 (69.3%) were male. Seventy patients (55.1%) exhibited a favorable response to TNT, while 57 patients (44.9%) demonstrated a poor response. Tumor characteristics, including diameter, distance from the anal verge, pre-TNT lymphocyte, pre-TNT hemoglobin, CA199, PLR, and HALP, exhibit correlations with TNT-induced tumor regression. Multivariate logistic regression analysis identified large tumor diameters (> 5.0 cm; p = 0.005, HR 2.958; 95% CI 1.382-6.335) and low HALP (<= 40; p = 0.002, HR 0.261; 95% CI 0.111-0.612) as predictors of TNT-induced poor responses. Additionally, low levels of HALP were associated with an increased risk of recurrence in patients with LARC with TNT, but this was not statistically significant (p = 0.087, HR 2.008, 95% CI 0.906-4.447). Conclusion: A large tumor diameter and low HALP predict poor tumor regression induced by the CAPOX-based TNT regimen in patients with LARC.